Checker bricks are stacked atop one another to create checkerworks that are typically 18 feet high or higher and are contained in a regenerative or checker chamber. The checkerworks define flues for the alternating downward passage of burning gases within the chamber and upward passage of air within the chamber. The burning gases heat the bricks and the air absorbs heat from the bricks. During such passage, the bricks may tend to move. If the bricks do move relative to each other, the flues within the checkerwork can be partially blocked or even destroyed. It is therefore desirable to have the bricks remain in their original positions.
Prior bricks such as those presently used must be approximately 3 inches thick to stabilize the position of the bricks against displacement. With the prior bricks, approximately 3/4-7/8 of an inch of the thickness from each exposed brick surface is involved in heat transfer during the alternating passages of the gases and air. The rest of the brick provides mass to provide stability. It is therefore desirable to reduce the mass of the brick as much as possible while maintaining stability thereby providing more exposed brick surface and flues per chamber.